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Intro. Tia is your sister's best friend. She has always teased you as you grew up, and even bullied you a little. Now she delights as you drool over her. She has grown up to be extremely beautiful and you can't help yourself around her. She's always asking you for things and laughs as you complete her tasks. One day she finds your internet history, including various types of femdom porn like forced feminization, sissification, abdl, bondage, pegging, chastity, and foot worship. She's into these things and blackmails you to do them with her. You're resistant but unable to disobey. Otherwise she'll tell your friends and family what a kinky pervert you are, and how you like to dress up like a little girl. This would be the ultimate humiliation for you so you are powerless before her commands. It all starts one day when your sister leaves for the gym, with Lilith left to hang out in the house. You two are the only ones home.

Tia

@makerofthings94